Ismael Reyes Retana Tello

Partner, Mexico City


A client describes him as “very knowledgeable and up to date with the details of the cases and well regarded in the legal community.”
Chambers Latin America 2020


Ismael focuses on regulatory matters and administrative litigations. Ismael has a unique vision capable of seeing both sides of the coin a talent that comes from more than 25 years of experience working in the public sector and more than a decade at White & Case. This quality is praised by the clients, who highlight his "understanding of the spirit of the law and the ability to put it into practice in a pragmatic manner." Chambers Latin America, 2018

Clients who benefit from Ismael's experience include major financial institutions and corporations, such as Telefónica, Televisa, Kansas City Southern Mexico, the Confederation of Potato Producers and Izzi, as well as financial institutions and sovereign governments.

Recent matters include Ismael's successful representation of the Mexican division of Televisa and Telefónica, in a case heard by the Mexican Supreme Court. The court's ruling set a landmark precedent for the telecommunications industry in Mexico.

Noteworthy in his experience is Ismael's achievement of novel injunctions in constitutional matters. These involved several aspects new to Mexican Law, such as the defense of collective and extended rights, and innovative means to secure standing of his clients in courts. Ismael's innovative work was recognized by The Financial Times Innovative Lawyers North America 2017 and 2019 reports in the in the "Rule of Law and Access to Justice" category.

During his time in the public sector, Ismael was considered a leading specialist in constitutional and administrative law in Mexico, acting first as Director General of Legal Studies of the Presidency, then as Deputy Legal Counsel to the President, and until 2008, as Federal Deputy Attorney General for Tax Matters and Deputy Counsel to the Ministry of Finance and Public Credit (Subprocurador Fiscal Federal).

Ismael served for nine years as the Presidential delegate before the Supreme Court of Justice of the Nation, managing constitutional controversies and preparing legislative bills. While working for the Office of the Counsel to the President and the Office of the Federal Attorney General for Tax Matters, he helped to develop several initiatives of constitutional and legal reform, and to draft Presidential decrees.

Formerly a respected academic, Ismael served as Professor of Constitutional Law at the Universidad Panamericana and Universidad Nacional Autónoma de México (UNAM); of Mexican Law History at the Universidad Iberoamericana, and of Human Rights at the Instituto Nacional de Capacitación Penitenciaria.

Ismael has authored several articles in trade magazines and newspapers; he has co-authored several books and he was Publishing Advisor for the Reforma newspaper in 2006, 2008 and 2011.

Ismael has worked on a pro bono basis for more than 50 organizations such as: Mexicanos Primero, Mexicanos Contra la Corrupción, Museo Universitario de Arte Contemporáneo (MUAC), Museo MACAY, Terremoto Magazzinne, and Comisión de Solidaridad y Defensa de los Derechos Humanos (Indígenas Rarámuris). He is trustee of the Board of Museo Tamayo and of Contemporary Art Patronage (Patronato de Arte Contemporáneo) and he is Member of the Board of SOMA and Desarrollo Confiable.

Bars and Courts
Authorized to practice law in Mexico
Diplomatic Studies
Instituto Matias Romero
Program on Human Rights (Diplomado en Derechos Humanos)
Universidad Iberoamericana
Attorney at Law (Abogado)
Universidad Panamericana


Altán Redes, 2018
Ismael represents Altán Redes as lead counsel and its advisor in the disputes initiated by Rivada Networks against the public tender and the award. This case includes complex and innovative problems in constitutional, telecommunications and public procurement matters. The successful representation of our client has allowed it to successfully start its operations in Mexico.

Historic victory at the Supreme Court of Justice for our client Servicio de Administración y Enajenación de Bienes (SAE), 2018
Consorcio Azucarero Caze filed numerous lawsuits against the bidding of various sugar mills that were awarded to four of the most important companies in the industry, which represented 22 percent of the country's sugar production. After several years of litigation, on February 21, 2018, White & Case achieved a decisive victory before the Supreme Court of Justice: the Court, in a split decision, denied Consorcio Azucarero Caze's claim to revert the property of the sugar mills, resolutions that will allow us to secure the sale of the sugar mills, which added up to almost USD 545 million.

 Tarifa Cero, 2018
Ismael represented Televisa and Telefónica in a high-profile contentious matter before the Supreme Court regarding zero termination rates (fixed and mobile). Thanks to our expert stewardship of this matter, Televisa and Telefónica secured a Supreme Court ruling that prohibits the dominant agent from collecting rates for interconnection services rendered from late 2014 to 2017 from other telecom providers.

Mexican potato farmers protecting local crops, 2014 – 2016 
Ismael obtained a precedent-setting injunction against the import of fresh potatoes into Mexico, which brought an end to a governmental policy that Mexican potato producers feared could have a devastating impact on their crops. In July 2016, a Federal Judge issued a final resolution favorable to Conpapa's interests. Based on the "in dubio pro natura" principle, a District Court in the State of Sinaloa suppressed the importation of fresh potatoes based on the threat of danger to the Mexican environment and to Mexican potato crops posed by the new ruling. Following the injunction, the new ruling will not be enforced in Mexico. 

Mexican Federal Court Orders Government to Continue Teacher Evaluation, 2015
Ismael represents Aprender Primero in a constitutional trial against the controversial announcement by Mexico's Ministry of Education to suspend teachers' evaluations indefinitely. Due to the suspension that was obtained, it was guaranteed that the teacher's evaluations continued. Such evaluations are a key pillar of the government's education reform as well as a constitutional obligation to ensure the quality of education rendered by public schools. 

Cancelación del proyecto Corredor Chapultpec, 2015
White & Case is representing several groups of neighbors in Mexico City against the urban development project known as the "Corredor Cultural Chapultepec-Zona Rosa" proposed by the Mexico City Government. This project had serious problems from an urban, environmental and cultural point of view. The injunction obtained halted definitively the implementation of the project.

Phone rates victory for Telefónica at Mexican Supreme Court, 2012
In a case heard by the Mexican Supreme Court, the court ruled to void the mobile termination rates that the Ministry of Communications and Transports required Telefónica to charge. The court's ruling set a landmark precedent for the telecommunications industry in Mexico because it recognized the full independence of the Federal Telecommunications Commission from the Ministry of Communications and Transports and gave mobile carriers more legal certainty.

"Plan" victory for Grupo Telefónica at Mexican Supreme Court, 2012
Ismael also represented Grupo Telefónica in litigation that obtained a favorable ruling, pursuant to which several dispositions of the Plan Técnico Fundamental de Interconexión e Interoperabilidad (the "Plan") issued by the FTC, were declared unconstitutional. Accordingly, Grupo Telefónica is the only telecommunications service provider in Mexico that is not required to comply with certain obligations set forth in the Plan. The Mexican Supreme Court issued a book entitled Relevant Decisions, which describes the aforementioned litigation as the cornerstone for setting innovative precedents and criteria regarding the authority of the FTC as regulator of the telecommunications sector.

Representations against National Departments, States and Municipal Governments, 2008 – 2013
Ismael has been active in other defense pleadings representing entities of the financial system against acts of the National Banking and Securities Commission, the Ministry of Treasury and the National Insurance and Bonding Commission, as well as state and municipal governments. He obtained a number of notable favorable rulings, including in two legal actions (amparos) filed on behalf of almost all Mexican banks against legislation of the Federal District and the municipality of Guadalajara.


Ismael has participated in the publication of several books:

UNO TV no es TV: Falló el Instituto Federal de Telecomunicaciones, published by Ed. Themis y BMA, 2016

Ismael wrote the foreword to El Chamizal, a 50 años de su devolución, Edited by the General Committee of the Chamber of Deputies, 2014

Authored an essay entitled "Endorsement of Broadcasting Concessions" for the Telecommunications Law Volume of the Obra Jurídica Enciclopédica, a collection of 43 volumes, published by Editorial Porrúa and the Escuela Libre de Derecho in tribute to the 100-year anniversary of the Escuela Libre de Derecho Law School

The Federal Court of Tax and Administrative Justice LXX years after the Tax Law Enactment, Ed. Tribunal Federal de Justicia Fiscal y Administrativa, México, 5 volumes, 2006, (Tribunal Federal de Justicia Fiscal y Administrativa a los LXX años de la Ley de Justicia Fiscal) (collective work)


Ismael has also written several essays, including:

"Energy reform: Notes about the constitutionality of a the employment of third parties in refining activities," Jurípolis, 2009, (La reforma energética: Apuntes sobre la constitucionalidad de la contratación de terceros en actividades de refinación) 

"Reflections regarding the interference of the Senate in the designation of employees of the Union," Nuestra Democracia, 2007, (Reflexiones en torno a la injerencia del Senado en el nombramiento de los empleados de la Unión)

"Historical development concerning the President's ability to make observations regarding the Federal Expense Budget," Revista Mexicana de Justicia, 2006, (Evolución histórica de la facultad del Presidente de la República para formula observaciones al Presupuesto de Egresos de la Federación)

"The scope of the resolution related to the constitutional controversy 91/2003," Nuestra Democracia, 2005, (Alcances de la resolución de la controversia constitucional 91/2003)

"Notes about the impacts of the resolutions regarding constitutional controversies and unconstitutionality actions," Jurípolis, 2005, (Apuntes sobre los efectos de las resoluciones en las controversias constitucionales y acciones de inconstitucionalidad)

"Renewal of the judicial review system," Nuestra Democracia, 2005, (La renovación del sistema de control constitucional)